Chapter 7Electrical resistivity methods

7.1 Introduction 4187.2 Basic principles 418

7.2.1 True resistivity 4187.2.2 Current flow in a homogeneous earth 424

7.3 Electrode configurations and geometric factors 4267.3.1 General case 4267.3.2 Electrode 4277.3.3 Media with contrasting resistivities 433

7.4 Modes of development 4417.4.1 Vertical electrical sounding (VES) 4417.4.2 Automated array scanning 4447.4.3 Constant-separation traversing (CST) 4467.4.4 Field problems 447

7.5 Interpretation methods 4537.5.1 Qualitative approach 4537.5.2 Master curves 4557.5.3 Curve matching by computer 4577.5.4 Equivalence and suppression 4617.5.5 Inversion, deconvolution and numerical

modelling 4647.6 Mise-a-la-masse method 4677.7 Applications and case histories 470

7.7.1 Engineering site investigations 4707.7.2 Groundwater and landfill surveys 4757.7.3 Glaciological applications 482

7.8 Electrokinetic (EK) surveying in groundwatersurveys 485

7.9 Leak detection through artificial membranes 488